The objector to a referendum concerning voting districts in Naperville withdrew all of his challenges to petition signatures Friday.

The move comes a day after the city's legal staff finished reviewing more than 2,000 signatures and leaves a handful of objections centered around whether the referendum question is valid.

In 2015, Naperville is scheduled to switch its City Council to a hybrid system that includes a mix of district and at-large representation following the results of a 2010 ballot question organized by the Naperville Voter Education League. Roughly 66 percent of voters in that election approved the switch.

But a group of residents then formed Yes at Large, which asserts voters did not have enough information about the pros and cons and that districts will be detrimental.

In late November, the group filed a referendum petition with 2,320 signatures, exceeding the 1,680 needed. However, resident Paul Sjordal filed an objection on Jan. 14 stating less than 900 of the signatures are valid and the referendum question is confusing.

Two members of city legal staff spent four hours reviewing signatures against Will County voter registration records this week. Four staff members then spent more than six hours reviewing DuPage County records.

On Friday, Sjordal's attorney Doug Ibendahl withdrew the objections related to the signatures.

"For the first time now this Friday afternoon he's now coming in after the time and money and effort has been spent to review the records," said Kevin McQuillan, attorney for Yes at Large co-chair Rebecca Boyd-Obarski.

City Attorney Margo Ely said she believes Ibendahl was withdrawing the objections because the records check shows there are enough valid signatures.

Ibendahl replied he has always said the electoral board should have considered the legal issues before reviewing the signatures and that removing the objections will help move the proceedings along.

"This case is so obvious on the law that what I'm saying is I'm trying to save everyone time and money and saying we can dispense with everything else and just focus on the issues that remain," he said.

Ely initially advised the board to keep the voter registration findings in the official record even if the objections are being withdrawn. But in a rare point of agreement, both attorneys said they did not want the findings on the signatures entered into the record. The board agreed to leave them out.

During the hour-long proceedings Friday, Councilman Doug Krause, who sits on the electoral board, also threatened to remove Ibendahl from the case after repeatedly speaking without permission. He also cited an assertion Ibendahl made earlier in the week that Ely was lying.

"We take this very seriously here and you continue to be combative, disrespectful," Krause said.

The hearings will resume at 2 p.m. Tuesday, when the board will decide whether the referendum question is valid. The question asks, "Shall the city of Naperville elect city council at large instead of part of the councilmen at large and part of the councilmen from districts?" Sjordal's objection argues it is "excessively vague and misleading."

The board also will consider whether to reimburse Boyd-Obarski's legal fees for the time McQuillan spent dealing with the objections Ibendahl withdrew.